Visceral organs within humans and other mammals rely on the flow of blood to function properly. Exemplary visceral organs include, but are not limited to, the pancreas, duodenum, small intestine, colon, liver, spleen, kidneys, adrenal glands, stomach, appendix, and gall bladder, among others.
In some cases, a visceral organ may experience ischemia, which is a restriction or obstruction of blood flow to that organ. Ischemia in a visceral organ may potentially damage the organ, exacerbate an existing detrimental condition, and/or cause pain.
An exemplary cause of ischemia is chronic pancreatitis. Chronic pancreatitis is an inflammatory condition that results in permanent structural changes in the pancreas. Clinical manifestations of this disorder include chronic abdominal pain and pancreatic exocrine and endocrine dysfunction.
One theory regarding the pathogenesis of chronic pancreatitis suggests that increased secretion of pancreatic proteins causes proteinaceous plugs to form within the interlobular and intralobular ducts of the pancreas. These plugs may acts as a nidus for calcification, leading to stone formation within the duct system. The net result is the formation of ductal epithelial lesions which scar and obstruct the pancreatic ducts, thereby causing inflammatory changes and cell loss.
When a patient suffers from a pancreatic or biliary duct obstruction, such as those associated with pancreatitis, the outflow of pancreatic secretions may be obstructed, thus causing increased intraductal pressure. This rise in intraductal pressure may induce or contribute to pancreatic ischemia, which may be a major factor in pain experienced by patients with chronic pancreatitis.
Pancreatic ischemia is typically treated by surgically decompressing ducts within the pancreas using a procedure known as a Puestow procedure. During a Puestow procedure, the abdomen is opened with an incision extending from the lower breastbone to the umbilicus. The pancreas is exposed and the main pancreatic duct is opened. The opened pancreatic duct is then connected to a loop of small intestine so that the pancreas drains directly into the intestines. This procedure is highly invasive and irreversibly reconstructs the organs of the gastrointestinal system. In addition, 11% to 56% of patients do not achieve adequate pain relief with initial operative treatment, and subsequent operations for recurring or persistent pain are common.